Radiation shields for furnaces

ABSTRACT

This invention relates to radiation shields for furnaces. Such shields are made of a removable ray protection element and a plurality of foil layers.

United States Patent [72] Inventors GerolfStrohmeier; [50] Field of 263/50; Alfred Pohler, Reutte, Austria 126/202; 250/108 X XX 05500 5 55 3 33 6 66 2 22 m S "mm m .l T u H P m. .m d m nnnun n T "uh a M u n m A .m h n 6 mt m m mm C e m 0 SE r m MU Tamas m m em nm fTc Sa .mSmvu m g\ BD 8.110 .16 MTLCBmm i M56770 J N66666 99999 u 1111] ng r 5 567 mo mM 033 5 69043 ,529 W 55776 am I 88 25 m 6 J nn B. 33333 PA n .m m w 0 C t k m 0 m Y n W e M v s mv I 67 m.Nm 990 m mu mm flw MSZMYMiM U mmm u 7 J mNaJAA 0. de N w w N m m P i m n AFPA P 11]] 1]] I253 23 2247 333 [iii [[I.

[54] RADIATION SHIELDS FOR FURNACES 5 Claims, 7 Drawing Figs.

[51] Int Cl 263/50 ABSTRACT: This invention relates to radiation shields for F23n 9/00, furnaces. Such shields are made of a removable ray protection element and a plurality of foil layers.

PATENTEU JAN26 ISII 3558.113

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A4 FRED Pal/L 52 RADIATION SHIELDS FOR FURNACES Radiation shields for furnaces usually consist of a plurality of concentric metal cylinders interconnected with spacers. The cylinders. when small enough, can be produced from a single sheet although for larger size cylinders several sheets have to be connected together by riveting or welding. Such conventional radiation shields are expensive to produce and are also disadvantageous. Thermal tensions form in the radiation shield resulting in deformation and cracking of the cylinder metal. In addition, such materials as molybdenum and tungsten, when present as the metallic component of radiation shields, recrystallize at high working temperatures and ultimately become very brittle and hence ineffective. Such fixed radiation shields also develop rough inner surfaces reducing the desired reflection. In addition, the radiation shields, due to the concentric metal cylinders, are very heavy and cumbersome.

Radiation shields made of multilayers of metal foil are found to be unsatisfactory since they become brittle when exposed to the heat zone of the furnace and, in addition, the surface layers of the foil tend to adhere and become welded together thereby losing efficiency.

The present invention does not suffer from the disadvantages of the prior, art system. In accordance with the present invention, radiation shields contain a frame of a high temperature resistance material which is covered on the side of exposure to rays with removable metallic ray protection elements and on the cooler side, the side away from the rays, with several spaced apart layers of metal foil.

Since the metallic ray protection elements are removable they can easily be removed and new elements inserted when necessary rather than having to replace the entire shield. The frame itself is protected from the highest furnace temperatures and hence need not be replaced, and the foil layers, while not exposed to the highest furnace temperatures and therefore not subjected to the extreme conditions that previously caused breakdown of foil parts, nevertheless operate, to produce their shielding effect in a very satisfactory manner. The foil layers are arranged on a part of the radiation shield where they are exposed to relatively lower temperature.

The metallic ray protection elements are made of high melting point materials having satisfactory radiation shielding properties in accordance with prior art techniques. Preferably the metal should have a melting point in excess of about 2500 C. Such materials as tungsten, molybdenum and tantalum are particularly useful. Ceramic materials can also be used where desired.

The frame should be made of suitable high temperature resistance materials as well.

The foil components can be any of the foil materials known to the art for use in radiation shielding.

The invention is further illustrated by reference to the drawings:

FIGS. 1 and 2 illustrate the frame of the radiation shield;

FIG. 3 is a cross-sectional view of the complete radiation shield showing the frame, shielding elements and foil layers in lace; p FIGS. 4, 5 and 6 are sectional views of a shielding element; and

FIG. 7 illustrates the arrangement of the radiation shield elements on a frame body with even surface.

As shown in FIGS. 1 and 2, the frame can be fonned of a corrugated sheet of high melting metal. The shape of the frame is circular as shown in FIG. I, while in FIG. 2, the shape is shown to be generally square. The exact shape of the frame is relatively unimportant. The frame can be formed of a solid material or it can be made of wound or interwoven wire.

As shown in FIG. 3, the frame I is first formed as in the circular shape shown in FIG. 1. To stabilize the frame and to com nect it with the other parts of the radiation shield. wire rings 2 and 3 are provided. The wire rings can be anchored either through holes in frame I or secured through the use of bolts or eyelets 4. Several wire rings can be-arranged one over the other.

On the inner wire ring 2, the heating shield elements 5 are attached. The radiation shield elements need not be in one piece and preferably will not be, to insure ease of removal. A suitable means of attaching theradiation shield elements 5 is shown in FIGS. 4, 5 and 6. Each of the separate radiation shield elements 5 is provided with lugs 6 which can be at tached to the wire rings 2. As can be seen, the individual elements 5 can easily be replaced and removed when desired.

The radiation shield elements 5 are arranged in a fashion similar to shingles on a roof such that each overlaps the next and covers the inner side of the frame completely.

A plurality of layers of foil 7 are imposed over the frame I and can be attached through the use of wire connectors or other devices to the wire rings 3. To protect the foil from physical harm, the radiation shields can be covered with a metal sheet coating 8.

It will be easily understood that other variations of this basic concept can be made and consequently it is not intended that *this invention be limited by the specific embodiments disclosed in the drawings.

We claim:

I. A radiation shield for the attenuation of radiation emitted from furnaces comprising:

a. a free standing frame member that completely encircles said furnace; continuous inner ring members affixed to the inner portion of said frame structure to structurally reinforce said frame structure, said inner ring members completely encircling said furnace;

. Continuous outer ring members affixed to the outer portion of said frame structure to structurally reinforce said frame structure, said outer ring members completely encircling said furnace; shielding elements being rectangular in shape and having a concaved curvature removably affixed to and in a spa cial relationship from said inner ring members so as to be positioned between said free standing frame member and said furnace with the concavity exposed to said furnace, said shielding elements overlapping with respect to each other so as to provide a continuous shielding surface that completely encircles said furnace; and foil layers removably affixed to and in a spacial relationship from said outer ring member, said foil layers completely encircling said furnace.

2. A radiation shield as described in claim I wherein said shielding elements act as a thermal absorbing barrier between said furnace and said foil layers.

3. A radiation shield as described in claim 2 wherein said free standing frame member is formed to define a corrugated pattern which closes upon itself.

4. A radiation shield as described in claim 3 wherein said free standing frame member defines a rectangular cross section.

5. A radiation shield as described in claim 3 wherein said free standing frame member defines a circular cross section.

mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent: No. 3,558,113 Dated January 26, 1971 Inventor(a) Gerolf Strohmeier and Alfred Pohler It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

an the first page, under "Assignee", the statement "a corpo'. of New York" should read a corporation of Maryland Signed and sealed this 21st day of September 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Acting Commissioner of Patem 

1. A radiation shield for the attenuation of radiation emitted from furnaces comprising: a. a free standing frame member that completely encircles said furnace; b. continuous inner ring members affixed to the inner portion of said frame structure to structurally reinforce said frame structure, said inner ring members completely encircling said furnace; c. Continuous outer ring members affixed to the outer portion of said frame structure to structurally reinforce said frame structure, said outer ring members completely encircling said furnace; d. shielding elements being rectangular in shape and having a concaved curvature removably affixed to and in a spacial relationship from said inner ring members so as to be positioned between said free standing frame member and said furnace with the concavity exposed to said furnace, said shielding elements overlapping with respect to each other so as to provide a continuous shielding surface that completely encircles said furnace; and e. foil layers removably affixed to and in a spacial relationship from said outer ring member, said foil layers completely encircling said furnace.
 2. A radiation shield as described in claim 1 wherein said shielding elements act as a thermal absorbing barrier between said furnace and said foil layers.
 3. A radiation shield as described in claim 2 wherein said free standing frame member is formed to define a corrugated pattern which closes upon itself.
 4. A radiation shield as described in claim 3 wherein said free standing frame member defines a rectangular cross section.
 5. A radiation shield as described in claim 3 wherein said free standing frame member defines a circular cross section. 